Topographical Features of the New Haven region. 91 



ous in the rippled surface of the little streamlet which flows along' it; the increase 

 of height thereby at the crossing- of the road to Pine Rock (3-SO from O. P., in 

 Table I) is at least 3 feet; and beyond this to the north the slope of the meadows 

 runs parallel closely with that of the terrace plain either side, the height of the 

 plain, even to its northern extremity, above the meadows being quite uniformly 

 31 to 32 feet. 



The observations show that the plain rises gradually to the north- 

 ward. The average increase of eleviition from Oyster Point to the 

 mouth of Pine-Marsh Creek, a distance of five miles, is 10 feet per 

 mile. From Oyster Point to York street, two miles, it is 8|feet; 

 and to College street nearly 1^ feet ; from College street to the Avest 

 end of the Munson street crossing of the Beaver Pond meadows, one 

 mile, it is only 6 feet ; along the Beavei- Pond basin, from its south- 

 ern end to the I'oad which crosses it a little south of the line of Pine 

 Kock, a mile in distance, the rise is 1 3-|- feet ; along the valley of Pine- 

 Marsh Creek, the average per mile is about 12 feet. The slope for a 

 mile north of College street, that is, between 1-80 and 2-80 miles in 

 latitude from Oyster Point, is more gradual than either to the north 

 or south ; and the same is true for a surface of like latitude near West 

 river, on which the increase in elevation from Oak street (1"85) to 

 Westville (3-15), 1-30 miles in distance, is only 8^ feet. 



The fact that the increase of elevation northward is by a gradual 

 slope, a}id not througJi a succession of two or more ahrupt terraces, is 

 manifest along Dixwell Avenue (the road to Ilamden Plains). The 

 Avenue lies to the east of the Beaver Pond Meadows, and to the west 

 of Pine-Marsh Creek, and extends northward in a nearly straight line, 

 bej^ond the mouth of Pine-Marsh Creek; and hence any terrace 

 would be apparent along its cou.rse, or in the fields either side, if such 

 existed. 



The observations prove the fact of an elevation of the land along 

 this part of Connecticut after the Champlain era, the era in which the 

 drift formation was made. They also appear to prove that this eleva- 

 tion was greatest, by a nearly regular rate, to the north. But before 

 arriving at any conclusions as to the amount of elevation, or its rate 

 of increase northward, it is necessary to consider: 



First, Whether part of the slope above pointed out did not exist 

 in the surface before the elevation began. 



Secondly, Whether part of the slope was not formed by the retreat- 

 ing waters during the ])rogress of the elevation. 



Tlnrdly, Whether part is not a result of a sinking of the more 

 southern portion of the plain since the elevation. 



